Compressed air operable inner vibrator for compacting concrete and the like

ABSTRACT

A compressed air operable inner vibrator for compacting concrete or the like, which includes an unbalance body, e.g. a ball, that circulates on an endless track on the inner side of the vibrator housing, and which also includes an automatically operating lubricating system for the unbalance body, which lubricating system comprises a reservoir for a lubricant and a throttled connecting passage between the reservoir and the track for the unbalance body and controls the release of lubricant to the unbalance body in conformity with the variable air pressure in the chamber in which the unbalance body circulates on the endless track.

United States Patent Uebel Sept. 30, 1975 [5 COMPRESSED AIR OPERABLE INNER 3,601,368 8/1971 Uebel 259/1 R VIBRATOR FOR COMPACTING 3,727,890 4/1973 Seidl et al. 259/] R CONCRETE AND THE LIKE Philipp Uebel, Munich, Germany Wacker Werke KG, Munich, Germany Filed: July 2, 1973 Appl. No.: 375,377

Inventor:

Assignee:

Foreign Application Priority Data July 6, 1972 Germany 2233235 Primary E.\'c1minerRobert D. Baldwin Attorney, Agent, or FirmWalter Becker 5 7 ABSTRACT A compressed air operable inner vibrator for compacting concrete or the like, which includes an unbalance body, e.g. a ball, that circulates on an endless track on the inner side of the vibrator housing, and which also includes an automatically operating lubrieating system for the unbalance body, which lubricating system comprises a reservoir for a lubricant and a throttled connecting passage between the reservoir and the track for the unbalance body and controls the release of lubricant to the unbalance body in conformity with the variable air pressure in the chamber in which the unbalance body circulates on the endless track.

1 Claim, 1 Drawing Figure US. Patent Sept. 36,1975 3,908,965

COMPRESSED AIR OPERABLE INNERVIBRATOR FOR COMPACTING CONCRETE AND THE LIKE The present invention relates to a compressed air operable inner vibrator for compacting concrete and the like which is provided with an unbalance body which is acted upon by compressed air and rolls on an annular path in the housing.

Inner vibrators of this type are lowered into the material to be compacted for compacting the respective material, such as concrete. These inner vibrators have a diameter which is relatively small with'regard to their length and are suspended in the extension of the compressed air feeding line-on the latter. A turning handle for turning-off and turning-on the compressed air is built into the compressed air feeding line in spaced relationship to the vibrator'proper. Thevibrators are closed by a closure cap at their front end on the end face facing away from the compressed air feeding line. After this closure cap has been removed, the inner parts of the vibrator are accessible.

Inner vibrators of thistype are generally known and are designated as vibrator bottles.

Heretofore, the moving parts of the compressed'air operable inner vibrators were lubricated by the oil contained in the compressed air so that they would remain operable. The oil was introduced into the compressed air by special oilers which were installed either at the place where the compressed air was generated or, if long compressed air feeding lines were involved, were placed into the turning handle of the compressed air shut-off valve which latter was located in the compressed air feedingline. At any rate, heretofore additional expensive structural elements were needed for this purpose which additional structural elements added considerably to the costs for thedevice. Moreover, special instructions had to be-.closely followed, for instance in connection with the installation of conduit oilers, in order to assure a reliable lubrication.

Oilers built into the handle have the additional drawback that they lubricate continuously during the operation and thus have a considerable oil consumption because the major portion of the oil is, without being used, blown out together with the exhaust air.

It is, therefore, an object of the present invention to provide a compressed air operable inner vibrator which will make it possible at considerably lower costs than heretofore to bring about a satisfactory but thrifty lubrication of all moving elements as well as of their cooperating parts and seats.

This object and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawing which illustrates primarily a longitudinal section through an inner vibrator according to the invention.

The inner vibrator according to the present invention is characterized primarily in that an automatically operable lubricating system for the unbalance body, the annular path and other elements liable to wear and rust, is built into the closure cap provided at the front end face of the vibrator housing which front end face faces away from the compressed air feeding line.

The installation of a lubricating system into the closure cap assures the shortest distance to the parts to be lubricated while the automatic operation of the lubricating system will assure a satisfactory lubrication at minimum oil consumption. This low oil consumption in its turn makes it possible that the lubricating system can be built into the closure cap. This is possible only when the oil supply to be stored in the closure cap will last for a relatively long time.

According to a very important further development of the invention, the lubricating system may be controlled by the variable air pressure which prevails in the space or chamber in which the unbalance body is running. To this end, it is provided, according to a further development of the invention, that the lubricating system consists of a storage chamber containing the oil and an air cushion and of a throttled connecting passage connecting the storage chamber and the chamber of the unbalance body.

The air pressure in the chamber in which the unbalance body is running is dependent on the condition of operation of the inner vibrator. When the inner vibrator is in operation, which means that the compressed air supply is turned on and that the unbalance body rotates on the annular path in the housing under the influence of the usually tangentially acting air pressure, the pressure in the chamber of the unbalance body is considerably higher than atmospheric pressure. This pressure will drop to atmospheric pressure when the supply of compressed air is turned off. This change in the air pressure can be taken advantage of in various ways for an automatic control of the lubricating system. In this connection, the above mentioned lubricating system consisting of storage chamber with air cushion and connecting passage excells by its extreme simplicity and has proved in practice to be highly satisfactory in operation.

The lubricating system according to the present invention operates according to the simple principle that at high pressure in the chamber of the unbalance body, in other words with the inner vibrator in operation, through the connecting passage also the pressure of the air cushion in the oil storage chamber will increase to a corresponding value, and that after the supply of compressed air has been shut off and consequently the pressure in the chamber for the unbalance body has dropped, a pressure equalizing air flow from the oil storage chamber through the throttled connecting passing into the chamber of the unbalance body will occur and the oil droplets will be pulled out of the oil storage chamber and will be conveyed into the chamber for the unbalance body, and will also be conveyed into the passages communicating therewith and to the other moving parts of the inner vibrator. In this way, with each turning off of the inner vibrator, a slight but sufficient lubrication of all parts is effected which would otherwise be endangered by wear or rust and which are. located in the interior of the vibrator. In this connection, the oil consumption is so low that the oil stored in the closure cap will last for a long time. Tests which have been carried out with an inner vibrator according to the invention have proved that in excess of 100,000 turning-on and turning-off operations can be made without exhausting the oil reservoir in the closure cap. The subsequent disassembly of the inner vibrator revealed a proper oil film on all moving parts.

In order not to have to make the throttling area in the connecting passage too narrow in an endeavor to avoid an undesired great oil discharge from the storage chamber into the chamber for the unbalance body, which narrow passage would result in a clogging up, and furthermore in order to obtain a precisely controllable dosing of the lubricating oil, it is suggested, according to a further feature of the invention, to install in the connecting passage a stopper adapted to be wetted by the oil in the storage chamber. Such stopper may consist of any suitable air-permeable material having a suction effect. This stopper represents an effective closure means against the free passage of oil from the storage chamber into the chamber in which the unbalance body is running, and such stopper will not be an obstacle or impedement for the air current which occurs during the pressure equalization between the storage chamber and the chamber for the unbalance body. This air current will tear oil out of the stopper which had been drawn thereinto during the preceding working operation so that a desired dosing will be realized.

Referring now to the drawing in detail, the inner vibrator illustrated therein comprises a housing mantle l. The inner vibrator, when being lowered into the material to be compacted, is suspended on the air feeding and withdrawing line 2. The inner vibrator also comprises a front closure cap 3 and a running chamber 4 for the unbalance body 5. The roller path 6 for the unbalance body is provided on the interior of the housing mantle 1. The inner vibrator according to the invention furthermore comprises an oil storage chamber 7. The drawing shows the oil 8 in the storage chamber 7 in a position in which the oil will be when the device is in its position of use. The oil storage chamber 7 furthermore comprises an air cushion 9. The oil storage chamber 7 communicates with the chamber 4 through a connecting passage 10 which latter has built thereinto a stopper 11 made of an air-permeable material with a suction effect, for instance, felt. The compressed air which acts tangentially upon the unbalance body, in this instance a ball, is blown into the chamber 4 through the air nozzle 12. The discharge passage 13 discharges the air from the chamber 4.

As will be evident from the above, a lubrication will be carried out only when air passes from the storage chamber 7 into the chamber 4. This is the case each time when, following the condition of high pressure in the storage chamber 7 and in the chamber 4, the pressure in chamber 4 drops, in other words, each time after the supply of compressed air through nozzle 12 to the ball 5 is turned off.

It is, of course, to be understood that the present invention is, by no means, limited to the specific showing in the drawing but also comprises any modifications within the scope of the appended claims.

What I claim is:

l. A compressed air operable inner vibrator for compacting material, especially concrete, which includes in combination: housing means comprising an operating chamber with an endless path, and an unbalance body arranged in said operating chamber and operable to circulate along said endless path, said housing means having one end provided with inlet and outlet conduit means for respectively conveying compressed air into and releasing air from said operating chamber, said housing means also having another end remote from said one end and located in the vicinity of said operat ing chamber, closure cap means arranged at and closing said other end and the improvement therewith comprising means forming a lubricating system with said cap means including a reservoir for storing lubricant built into said cap means, and lubricant control means interposed between said operating chamber and said reservoir and operable automatically to bring about a transfer of lubricant from said reservoir to said operating chamber in response to air pressure variations in said operating chamber, said lubricant control means including an air cushion in said reservoir and throttled conveying conduit means between said reservoir and said operating chamber, and stopper means of hydroscopic air permeable material arranged in said conveying conduit means and adopted to be wetted by lubricant from said reservoir. 

1. A compressed air operable inner vibrator for compacting material, especially concrete, which includes in combination: housing means comprising an operating chamber with an endless path, and an unbalance body arranged in said operating chamber and operable to circulate along said endless path, said housing means having one end provided with inlet and outlet conduit means for respectively conveying compressed air into and releasing air from said operating chamber, said housing means also having another end remote from said one end and located in the vicinity of said operating chamber, closure cap means arranged at and closing said other end and the improvement therewith comprising means forming a lubricating system with said cap means including a reservoir for storing lubricant built into said cap means, and lubricant control means interposed between said operating chamber and said reservoir and operable automatically to bring about a transfer of lubricant from said reservoir to said operating chamber in response to air pressure variations in said operating chamber, said lubricant control means including an air cushion in said reservoir and throttled conveying conduit means between said reservoir and said operating chamber, and stopper means of hydroscopic air permeable material arranged in said conveying conduit means and Adopted to be wetted by lubricant from said reservoir. 